improved indentation and whitespace for markdown code blocks

All code blocks in markdown have been intended by at least 4 spaces.

We add `--tab-stop=8` to all `pandoc(1)` executions in order to set
a better tab stop indentation, especially for tab intended code blocks.

Changed `bin/pandoc-wrapper.sh` VERSION from "1.5.3 2024-03-26"
to "1.6 2024-03-31".

Fixed `1991/brnstnd/sorta.README.md` so that the sorta code
is code blocks.

Removed unneeded paragraph group in copyright in `inc/footer.default.html`.

Fixed excess whitespace after list Author on entry `index.html` page.

Changed `bin/output-index-author.sh` VERSION from "1.5.2 2024-03-26"
to "1.6 2024-03-31".

Performed `make www` to perform the above and test under macOS.

TODO: Fix the problem of the initial line of code being extra intended.
TODO: Fix excess whitespace around code that is inline.

1998/bas2/index.html

@@ -132,8 +132,7 @@
 <h2 id="author"><a name="author"></a>Author:</h2>
 <ul>
 <li>Name: <a href="../../authors.html#Bas_de_Bakker">Bas de Bakker</a><br>
-Location: <a href="../../location.html#NL">NL</a> - <em>Kingdom of the Netherlands</em> (<em>Netherlands</em>)
-<br><br></li>
+Location: <a href="../../location.html#NL">NL</a> - <em>Kingdom of the Netherlands</em> (<em>Netherlands</em>)</li>
 </ul>
 
 <!-- END: next line ends content generated by: bin/output-index-author.sh -->
@@ -142,16 +141,16 @@ Location: <a href="../../location.html#NL">NL</a> - <em>Kingdom of the Netherlan
 <!-- START: this line starts content for HTML phase 21 by: bin/pandoc-wrapper.sh via bin/md2html.sh -->
 
 <h2 id="to-build">To build:</h2>
-<div class="sourceCode" id="cb1"><pre class="sourceCode sh"><code class="sourceCode bash"><span id="cb1-1"><a href="#cb1-1" aria-hidden="true" tabindex="-1"></a><span class="fu">make</span> all</span></code></pre></div>
+<div class="sourceCode" id="cb1"><pre class="sourceCode sh"><code class="sourceCode bash"><span id="cb1-1"><a href="#cb1-1" aria-hidden="true" tabindex="-1"></a>    <span class="fu">make</span> all</span></code></pre></div>
 <h2 id="to-use">To use:</h2>
-<div class="sourceCode" id="cb2"><pre class="sourceCode sh"><code class="sourceCode bash"><span id="cb2-1"><a href="#cb2-1" aria-hidden="true" tabindex="-1"></a><span class="ex">./bas2</span> <span class="op">&lt;</span> file</span>
-<span id="cb2-2"><a href="#cb2-2" aria-hidden="true" tabindex="-1"></a><span class="bu">echo</span> text <span class="kw">|</span> <span class="ex">./bas2</span></span></code></pre></div>
+<div class="sourceCode" id="cb2"><pre class="sourceCode sh"><code class="sourceCode bash"><span id="cb2-1"><a href="#cb2-1" aria-hidden="true" tabindex="-1"></a>    <span class="ex">./bas2</span> <span class="op">&lt;</span> file</span>
+<span id="cb2-2"><a href="#cb2-2" aria-hidden="true" tabindex="-1"></a>    <span class="bu">echo</span> text <span class="kw">|</span> <span class="ex">./bas2</span></span></code></pre></div>
 <h2 id="try">Try:</h2>
-<div class="sourceCode" id="cb3"><pre class="sourceCode sh"><code class="sourceCode bash"><span id="cb3-1"><a href="#cb3-1" aria-hidden="true" tabindex="-1"></a><span class="ex">./try.sh</span></span>
+<div class="sourceCode" id="cb3"><pre class="sourceCode sh"><code class="sourceCode bash"><span id="cb3-1"><a href="#cb3-1" aria-hidden="true" tabindex="-1"></a>    <span class="ex">./try.sh</span></span>
 <span id="cb3-2"><a href="#cb3-2" aria-hidden="true" tabindex="-1"></a></span>
-<span id="cb3-3"><a href="#cb3-3" aria-hidden="true" tabindex="-1"></a><span class="ex">./try.sh</span> <span class="st">&quot;foo bar&quot;</span> <span class="st">&quot;baz&quot;</span> <span class="st">&quot;IOCCC 1998/bas2&quot;</span> README.md</span>
+<span id="cb3-3"><a href="#cb3-3" aria-hidden="true" tabindex="-1"></a>    <span class="ex">./try.sh</span> <span class="st">&quot;foo bar&quot;</span> <span class="st">&quot;baz&quot;</span> <span class="st">&quot;IOCCC 1998/bas2&quot;</span> README.md</span>
 <span id="cb3-4"><a href="#cb3-4" aria-hidden="true" tabindex="-1"></a></span>
-<span id="cb3-5"><a href="#cb3-5" aria-hidden="true" tabindex="-1"></a><span class="ex">./try.sh</span> try.sh <span class="st">&quot;bas2.c&quot;</span> bas2.orig.c</span></code></pre></div>
+<span id="cb3-5"><a href="#cb3-5" aria-hidden="true" tabindex="-1"></a>    <span class="ex">./try.sh</span> try.sh <span class="st">&quot;bas2.c&quot;</span> bas2.orig.c</span></code></pre></div>
 <h2 id="judges-remarks">Judges’ remarks:</h2>
 <h3 id="questions-to-ponder">Questions to ponder:</h3>
 <p>Can you determine the relationship between the input and the resulting numeric